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Hi everybody
I have been trying to do DFT+U calculations for UO2 system but it didnt give the same results wtih literature. Here are my input files for band structure calculation.

First SC step:

POSCAR

UO2_work
5.51
0.0 0.5 0.5
0.5 0.0 0.5
0.5 0.5 0.0
1 2
Selective Dynamics
Direct
0.0 0.0 0.0 f f f
0.25 0.25 0.25 f f f
0.75 0.75 0.75 f f f

INCAR

SYSTEM = UO2_BULK
ISTART = 0
ICHARGE= 1
PREC = HIGH
ISMEAR = -5
NPAR = 1
LDAU = .TRUE.
LDAUL = 3 -1
LDAUU = 4.5 0
LDAUJ = 0.51 0
LMAXMIX = 6
LASPH = .TRUE.

KPOINTS

kpoints
0
Gamma
6 6 6
0 0 0

I copied the CHGCAR and WAVECAR to a second step NSC calculation and did the 2. step calculation with these INCAR and KPOINTS .

INCAR:

SYSTEM = UO2_BULK
ISTART = 0
ICHARGE= 11
PREC = HIGH
ISMEAR = 0
NPAR = 1
LDAU = .TRUE.
LDAUL = 3 -1
LDAUU = 4.5 0
LDAUJ = 0.51 0
LMAXMIX = 6
LASPH = .TRUE.

KPOINTS

k-points along high symmetry lines
10 ! 10 intersections
Line-mode
rec
0 0 0 ! gamma
0.5 0 0.5 !X

0.5 0 0.5 !X
0.5 0.5 0.5 ! L

0.5 0.5 0.5 ! L
0.5 0.25 0.75 !W

0.5 0.25 0.75 !W
0 0 0 ! gamma


It should give a band gap around 1.8 eV according to literature but this calculation gives the result as metallic.

So can anybody tell me please where my mistake is.

thank you all.

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